100pA～1μA量程的微弱电流源研制  

Development of Weak Current Source for Currents Between 100 pA and 1μA

作　　者：雷升杰[1] 魏志勇[1] 方美华[1] 陈国云[1] 张紫霞[1] 黄三玻[1] 

机构地区：[1]南京航空航天大学航天学院,江苏南京210016

出　　处：《计量学报》2013年第3期272-277,共6页Acta Metrologica Sinica

摘　　要：为了实现对微弱测量仪器进行测试与校准，根据恒流源电路的思想，研制了一种由运算放大器构成的微弱电流源。在微弱电流产生中，利用恒压源和高精度标准电阻，通过弘，变换来实现微弱电流的输出；设计反馈调节网络，来解决普通电流源实现微弱电流输出易受负载影响的缺点，消除负载对输出电流的影响，同时，实现100pA-1μA量程的微弱电流输出。为提高电流源的性能，电路中采取了屏蔽和滤波处理，来解决噪声的影响。经过测试，结果表明该电路的电流范围在100pA～1μA之间，电流源稳定可靠。在1nA时，误差不超过0．08nA。In order to test and calibrate the measuring instruments for weak current detection, a weak current source for currents between 100 pA and 1μA is developed, on the basis of the principle of constant-current source. A current source is built with operational amplifiers, resistors, constant voltage and standard resistance values to gain weak current output through V-I converter. A complete analysis for the dynamic properties of this current source, its equivalent relative error and circuit design are given. The effects of stray impedances on the behavior of the current source are taken into account and the techniques necessary to achieve an optimum stable performance, including processing noise effect are applied. Experiments show that the weak current source is stable and reliable, the output current range of the circuit is 10 pA ~ 10 μA. In 1 nA, the error is less than 0.08 nA.

关 键 词：计量学 微弱电流源 恒流源 V-I变换 噪声处理 

分 类 号：TB971[一般工业技术—计量学]